Explained: Why Do We Breathe?

Hello young learners, 

Welcome back to Kiki’s Knowledge Corner. I am happy to have helped you explore a wide variety of topics so far, ranging from Space to our Human body. I hope this has made your learning experience enjoyable as well. Today, let us explore a vital function of the human body – breathing. We all need to breathe in order to live. Have you ever wondered how our body processes the air that we breathe?

Let us learn together the science behind breathing.

Why do we breathe?

Every organ of our body needs oxygen. Oxygen is a gas that helps the organs to function properly. Right from digestion to thinking, all bodily functions need oxygen. Through the process of breathing, we take in oxygen. This process is called breathing in or inhalation. 

We also get rid of waste gas from our body called carbon dioxide while we breathe. This process is called breathing out or exhalation. In short, we inhale oxygen and exhale carbon dioxide. And the entire process is called respiration. From the outside, it looks like you breathe through your nose. However, respiration is a complex process that involves many other organs.

Which organs in our body help us breathe?

One cycle of respiration is around 5 to 6 seconds. The process in one cycle of respiration is: you inhale oxygen through your nose that travels to other organs using the bloodstream. The carbon dioxide from the organs travels back through the blood and comes out of your nose. The other organs inside our body- lungs, windpipe, diaphragm and brain- also carry out respiration. Let us look at how these organs work together.

The nose: The nose allows air to enter your body. The nasal hairs inside it filter the dust and moisten and warms the air that enters the lungs. 

The windpipe: The windpipe carries oxygen-rich air from your nose to your lung and releases carbon dioxide out of your lungs. 

The brain: Your brain constantly gets signals from your body about the amount of oxygen and carbon dioxide in your blood. In turn, it sends signals to the muscles involved in breathing and adjusts your breathing rate depending on what activity you are performing. Based on these signals, you inhale the right amount of oxygen needed.

The lungs: You have two lungs that take in air from the nose through the windpipe. These lungs are responsible for supplying oxygen to the organs and removing carbon dioxide from the organs. 

The diaphragm: The diaphragm is a dome-shaped, thin muscle that is found below the lungs. When you breathe in, the diaphragm contracts and pulls air into the lungs. When you exhale, the diaphragm relaxes and the air is forced out of the lungs. You will notice your chest cavity enlarge every time the diaphragm is at work.

How do we breathe in?

Your brain decides when it is time to breathe in. Signals from the respiratory centre in your brain travel through the nerves to your diaphragm and other muscles. 

The diaphragm acts first. It is pulled flat, thereby expanding the chest and drawing air into the lungs. At the same time, the air is pulled through your nose and into your windpipe. This later divides into airways supplying air to the left and right lungs.

Inside the lungs, there are more airways, which divide the air another 20 times. Then, the air goes through thousands of smaller airways and finally reaches the air sacs of the lungs. In this process, the air gets converted into oxygen, which later goes into the blood.

How do we breathe out?

 When you breathe out, the air sacs in the lungs relax and air moves out of the lungs. The diaphragm relaxes and the air is pushed out through the lungs, windpipe and out of your nose. The entire process is called exhalation or expiration, where the air laden with carbon dioxide (waste air), is pushed out of the body, and you are ready to inhale again.

Now that you know how we breathe, share other topics about the human body that you would like to know in the comments.